Near-inertial waves and microstructure mixing observations in the Beaufort Sea

In the Beaufort Sea in September of 2015, near-inertial internal waves (NIWs) generated by wind forcing events were observed by a mooring located at 72${}^{\circ }$ 35.646' N, 145${}^{\circ }$ 1.002' W. Microstructure measurements found moderately elevated (factor of 2-3 compared with background) turbulent dissipation rate ($ϵ$) from 20-150 m, reaching a maximum of $ϵ=6\times {10}^{-10}$ W kg${}^{-1}$ at 30 m depth. However, in spite of NIW velocity signals penetrating down to the Atlantic Water at 300 m, there was no evidence of elevated $ϵ$ associated with NIWs at these depths, and upwards heat flux out of the Atlantic Water was not enhanced in the presence of NIWs. Upper bounds on $ϵ$ determined by the decay of HKE with time were consistent with microstructure observations. A finescale parameterization based on both shear and strain measurements was applied. Above the Atlantic halocline at 200 m, agreement between the finescale parameterization and \textit{in situ} measurements of $ϵ$ was good; however, within and beneath the Atlantic halocline the finescale parameterization estimates were an order of magnitude lower than observations.